Wiring question about types and ratings

phishguy

Active Member
Finally getting to wiring my light and trying to finalize a plan of how I want to put it all together. Can I use the 18/2 with the full output of the driver? I am using a MW HLG-185h-48a ( 48v @ 4a )and running it to 4 CXM22 leds. What I am wondering if I can do is use that wire from the driver output about 8 feet away to a distribution block on my light where it will be split into 4 for parallel wiring. I have seen the wiring rated at 150v and 300v so I am not sure what to go by and how amps play in to those ratings. Also lastly, would I be ok using thermostat wiring for 120v @ 2a? Thank you for the help!
 

Nugachino

Well-Known Member
You're better off using the wire rated the same as what was supplied. Lower amperage wire is a fire hazard when given excess load.
 

Nugachino

Well-Known Member
4amp load.... okay. So. Probably better to have something that's a little higher than that. 6-8 amps rated.
 

CobKits

Well-Known Member
look at the rating stamped on the cable assembly. the thermostat wire i use and sell on the site is CMR/CLR2 rated - 300V

http://www.cerroretail.com/electrical/product-line/specialty-wire/thermostat/

voltage is a function of insulation

ampacity (i.e current carrying capacity) is a function of wire gauge, and is required to be reduced when 3 or more conductors are in a cable/conduit/etc. is not usually spec'd on cable because it varies how you use it (free air, conduit, buried, etc)

Note 8 to the ampacity tables in the NEC contains the requirement columns for derating ampacity because of adjacent current-carrying conductors. This note states that when the number of conductors in a raceway or cable exceeds 3, the ampacities are to be reduced by the appropriate percentage.

18 ga per NEC is 5.6A ampacity continuous. since there are only 2 conductors in t-stat cable it is rated for full 5.6A continuous. most of us run 2A or less so there is plenty of headroom.

http://www.cooperindustries.com/content/dam/public/bussmann/Electrical/Resources/solution-center/industrial_control_panels/BUS_Ele_Small_Conductor_Protection.pdf

for long runs always upsize your wires to reduce voltage drop. google "voltage drop calculator" theres tons of them online. if youre mounting a big high-current driver like an HLG 320 or 600 in another room, 12/2 romex is cheap and widely available

a 13A HLG-600-48 will lose 0.41V over 10 feet of 12 ga, but will lose 1.04V over 16GA - thats 17 watts thats going straight to heat, where it could be less than 6 with adequate wire sizing.

voltage drop is particularly important when youre running a driver near its voltage limit (like 50V cobs on a 48A, or 4 36V cobs on an 185-1400b
 
Last edited:

CobKits

Well-Known Member
Also lastly, would I be ok using thermostat wiring for 120v @ 2a? Thank you for the help!
if its on the AC side id just use regular 14, 16 ga grounded cable. you want 3 conductors and you want something durable since its AC. cut up an extension cord if you have to.
 

phishguy

Active Member
Thanks for the replies.. I was attempting to bring the DC voltage as well as AC for fan drivers to my light with a single 18/6 t-stat wire for simplicity.. I've realized it's not that much simpler than running proper wiring to the light so that's what I'm doing.. Thanks again for the replies!

Sent from my FRD-L04 using Rollitup mobile app
 
Top